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-rw-r--r--arch/mips/include/asm/uaccess.h791
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diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
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+++ b/arch/mips/include/asm/uaccess.h
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+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2007 Maciej W. Rozycki
+ * Copyright (C) 2014, Imagination Technologies Ltd.
+ */
+#ifndef _ASM_UACCESS_H
+#define _ASM_UACCESS_H
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <asm/asm-eva.h>
+#include <asm/extable.h>
+
+/*
+ * The fs value determines whether argument validity checking should be
+ * performed or not. If get_fs() == USER_DS, checking is performed, with
+ * get_fs() == KERNEL_DS, checking is bypassed.
+ *
+ * For historical reasons, these macros are grossly misnamed.
+ */
+#ifdef CONFIG_32BIT
+
+#ifdef CONFIG_KVM_GUEST
+#define __UA_LIMIT 0x40000000UL
+#else
+#define __UA_LIMIT 0x80000000UL
+#endif
+
+#define __UA_ADDR ".word"
+#define __UA_LA "la"
+#define __UA_ADDU "addu"
+#define __UA_t0 "$8"
+#define __UA_t1 "$9"
+
+#endif /* CONFIG_32BIT */
+
+#ifdef CONFIG_64BIT
+
+extern u64 __ua_limit;
+
+#define __UA_LIMIT __ua_limit
+
+#define __UA_ADDR ".dword"
+#define __UA_LA "dla"
+#define __UA_ADDU "daddu"
+#define __UA_t0 "$12"
+#define __UA_t1 "$13"
+
+#endif /* CONFIG_64BIT */
+
+/*
+ * USER_DS is a bitmask that has the bits set that may not be set in a valid
+ * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
+ * the arithmetic we're doing only works if the limit is a power of two, so
+ * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
+ * address in this range it's the process's problem, not ours :-)
+ */
+
+#ifdef CONFIG_KVM_GUEST
+#define KERNEL_DS ((mm_segment_t) { 0x80000000UL })
+#define USER_DS ((mm_segment_t) { 0xC0000000UL })
+#else
+#define KERNEL_DS ((mm_segment_t) { 0UL })
+#define USER_DS ((mm_segment_t) { __UA_LIMIT })
+#endif
+
+#define get_fs() (current_thread_info()->addr_limit)
+#define set_fs(x) (current_thread_info()->addr_limit = (x))
+
+#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg)
+
+/*
+ * eva_kernel_access() - determine whether kernel memory access on an EVA system
+ *
+ * Determines whether memory accesses should be performed to kernel memory
+ * on a system using Extended Virtual Addressing (EVA).
+ *
+ * Return: true if a kernel memory access on an EVA system, else false.
+ */
+static inline bool eva_kernel_access(void)
+{
+ if (!IS_ENABLED(CONFIG_EVA))
+ return false;
+
+ return uaccess_kernel();
+}
+
+/*
+ * Is a address valid? This does a straightforward calculation rather
+ * than tests.
+ *
+ * Address valid if:
+ * - "addr" doesn't have any high-bits set
+ * - AND "size" doesn't have any high-bits set
+ * - AND "addr+size" doesn't have any high-bits set
+ * - OR we are in kernel mode.
+ *
+ * __ua_size() is a trick to avoid runtime checking of positive constant
+ * sizes; for those we already know at compile time that the size is ok.
+ */
+#define __ua_size(size) \
+ ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
+
+/*
+ * access_ok: - Checks if a user space pointer is valid
+ * @addr: User space pointer to start of block to check
+ * @size: Size of block to check
+ *
+ * Context: User context only. This function may sleep if pagefaults are
+ * enabled.
+ *
+ * Checks if a pointer to a block of memory in user space is valid.
+ *
+ * Returns true (nonzero) if the memory block may be valid, false (zero)
+ * if it is definitely invalid.
+ *
+ * Note that, depending on architecture, this function probably just
+ * checks that the pointer is in the user space range - after calling
+ * this function, memory access functions may still return -EFAULT.
+ */
+
+static inline int __access_ok(const void __user *p, unsigned long size)
+{
+ unsigned long addr = (unsigned long)p;
+ return (get_fs().seg & (addr | (addr + size) | __ua_size(size))) == 0;
+}
+
+#define access_ok(addr, size) \
+ likely(__access_ok((addr), (size)))
+
+/*
+ * put_user: - Write a simple value into user space.
+ * @x: Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only. This function may sleep if pagefaults are
+ * enabled.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+#define put_user(x,ptr) \
+ __put_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * get_user: - Get a simple variable from user space.
+ * @x: Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only. This function may sleep if pagefaults are
+ * enabled.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+#define get_user(x,ptr) \
+ __get_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * __put_user: - Write a simple value into user space, with less checking.
+ * @x: Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only. This function may sleep if pagefaults are
+ * enabled.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+#define __put_user(x,ptr) \
+ __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * __get_user: - Get a simple variable from user space, with less checking.
+ * @x: Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only. This function may sleep if pagefaults are
+ * enabled.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+#define __get_user(x,ptr) \
+ __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct __user *)(x))
+
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#ifndef CONFIG_EVA
+#define __get_kernel_common(val, size, ptr) __get_user_common(val, size, ptr)
+#else
+/*
+ * Kernel specific functions for EVA. We need to use normal load instructions
+ * to read data from kernel when operating in EVA mode. We use these macros to
+ * avoid redefining __get_user_asm for EVA.
+ */
+#undef _loadd
+#undef _loadw
+#undef _loadh
+#undef _loadb
+#ifdef CONFIG_32BIT
+#define _loadd _loadw
+#else
+#define _loadd(reg, addr) "ld " reg ", " addr
+#endif
+#define _loadw(reg, addr) "lw " reg ", " addr
+#define _loadh(reg, addr) "lh " reg ", " addr
+#define _loadb(reg, addr) "lb " reg ", " addr
+
+#define __get_kernel_common(val, size, ptr) \
+do { \
+ switch (size) { \
+ case 1: __get_data_asm(val, _loadb, ptr); break; \
+ case 2: __get_data_asm(val, _loadh, ptr); break; \
+ case 4: __get_data_asm(val, _loadw, ptr); break; \
+ case 8: __GET_DW(val, _loadd, ptr); break; \
+ default: __get_user_unknown(); break; \
+ } \
+} while (0)
+#endif
+
+#ifdef CONFIG_32BIT
+#define __GET_DW(val, insn, ptr) __get_data_asm_ll32(val, insn, ptr)
+#endif
+#ifdef CONFIG_64BIT
+#define __GET_DW(val, insn, ptr) __get_data_asm(val, insn, ptr)
+#endif
+
+extern void __get_user_unknown(void);
+
+#define __get_user_common(val, size, ptr) \
+do { \
+ switch (size) { \
+ case 1: __get_data_asm(val, user_lb, ptr); break; \
+ case 2: __get_data_asm(val, user_lh, ptr); break; \
+ case 4: __get_data_asm(val, user_lw, ptr); break; \
+ case 8: __GET_DW(val, user_ld, ptr); break; \
+ default: __get_user_unknown(); break; \
+ } \
+} while (0)
+
+#define __get_user_nocheck(x, ptr, size) \
+({ \
+ int __gu_err; \
+ \
+ if (eva_kernel_access()) { \
+ __get_kernel_common((x), size, ptr); \
+ } else { \
+ __chk_user_ptr(ptr); \
+ __get_user_common((x), size, ptr); \
+ } \
+ __gu_err; \
+})
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ int __gu_err = -EFAULT; \
+ const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
+ \
+ might_fault(); \
+ if (likely(access_ok( __gu_ptr, size))) { \
+ if (eva_kernel_access()) \
+ __get_kernel_common((x), size, __gu_ptr); \
+ else \
+ __get_user_common((x), size, __gu_ptr); \
+ } else \
+ (x) = 0; \
+ \
+ __gu_err; \
+})
+
+#define __get_data_asm(val, insn, addr) \
+{ \
+ long __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: "insn("%1", "%3")" \n" \
+ "2: \n" \
+ " .insn \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " move %1, $0 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " "__UA_ADDR "\t1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=r" (__gu_tmp) \
+ : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
+ \
+ (val) = (__typeof__(*(addr))) __gu_tmp; \
+}
+
+/*
+ * Get a long long 64 using 32 bit registers.
+ */
+#define __get_data_asm_ll32(val, insn, addr) \
+{ \
+ union { \
+ unsigned long long l; \
+ __typeof__(*(addr)) t; \
+ } __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: " insn("%1", "(%3)")" \n" \
+ "2: " insn("%D1", "4(%3)")" \n" \
+ "3: \n" \
+ " .insn \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " move %1, $0 \n" \
+ " move %D1, $0 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
+ : "0" (0), "r" (addr), "i" (-EFAULT)); \
+ \
+ (val) = __gu_tmp.t; \
+}
+
+#ifndef CONFIG_EVA
+#define __put_kernel_common(ptr, size) __put_user_common(ptr, size)
+#else
+/*
+ * Kernel specific functions for EVA. We need to use normal load instructions
+ * to read data from kernel when operating in EVA mode. We use these macros to
+ * avoid redefining __get_data_asm for EVA.
+ */
+#undef _stored
+#undef _storew
+#undef _storeh
+#undef _storeb
+#ifdef CONFIG_32BIT
+#define _stored _storew
+#else
+#define _stored(reg, addr) "ld " reg ", " addr
+#endif
+
+#define _storew(reg, addr) "sw " reg ", " addr
+#define _storeh(reg, addr) "sh " reg ", " addr
+#define _storeb(reg, addr) "sb " reg ", " addr
+
+#define __put_kernel_common(ptr, size) \
+do { \
+ switch (size) { \
+ case 1: __put_data_asm(_storeb, ptr); break; \
+ case 2: __put_data_asm(_storeh, ptr); break; \
+ case 4: __put_data_asm(_storew, ptr); break; \
+ case 8: __PUT_DW(_stored, ptr); break; \
+ default: __put_user_unknown(); break; \
+ } \
+} while(0)
+#endif
+
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#ifdef CONFIG_32BIT
+#define __PUT_DW(insn, ptr) __put_data_asm_ll32(insn, ptr)
+#endif
+#ifdef CONFIG_64BIT
+#define __PUT_DW(insn, ptr) __put_data_asm(insn, ptr)
+#endif
+
+#define __put_user_common(ptr, size) \
+do { \
+ switch (size) { \
+ case 1: __put_data_asm(user_sb, ptr); break; \
+ case 2: __put_data_asm(user_sh, ptr); break; \
+ case 4: __put_data_asm(user_sw, ptr); break; \
+ case 8: __PUT_DW(user_sd, ptr); break; \
+ default: __put_user_unknown(); break; \
+ } \
+} while (0)
+
+#define __put_user_nocheck(x, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __pu_val; \
+ int __pu_err = 0; \
+ \
+ __pu_val = (x); \
+ if (eva_kernel_access()) { \
+ __put_kernel_common(ptr, size); \
+ } else { \
+ __chk_user_ptr(ptr); \
+ __put_user_common(ptr, size); \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_check(x, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ int __pu_err = -EFAULT; \
+ \
+ might_fault(); \
+ if (likely(access_ok( __pu_addr, size))) { \
+ if (eva_kernel_access()) \
+ __put_kernel_common(__pu_addr, size); \
+ else \
+ __put_user_common(__pu_addr, size); \
+ } \
+ \
+ __pu_err; \
+})
+
+#define __put_data_asm(insn, ptr) \
+{ \
+ __asm__ __volatile__( \
+ "1: "insn("%z2", "%3")" # __put_data_asm \n" \
+ "2: \n" \
+ " .insn \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__pu_err) \
+ : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
+ "i" (-EFAULT)); \
+}
+
+#define __put_data_asm_ll32(insn, ptr) \
+{ \
+ __asm__ __volatile__( \
+ "1: "insn("%2", "(%3)")" # __put_data_asm_ll32 \n" \
+ "2: "insn("%D2", "4(%3)")" \n" \
+ "3: \n" \
+ " .insn \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous" \
+ : "=r" (__pu_err) \
+ : "0" (0), "r" (__pu_val), "r" (ptr), \
+ "i" (-EFAULT)); \
+}
+
+extern void __put_user_unknown(void);
+
+/*
+ * We're generating jump to subroutines which will be outside the range of
+ * jump instructions
+ */
+#ifdef MODULE
+#define __MODULE_JAL(destination) \
+ ".set\tnoat\n\t" \
+ __UA_LA "\t$1, " #destination "\n\t" \
+ "jalr\t$1\n\t" \
+ ".set\tat\n\t"
+#else
+#define __MODULE_JAL(destination) \
+ "jal\t" #destination "\n\t"
+#endif
+
+#if defined(CONFIG_CPU_DADDI_WORKAROUNDS) || (defined(CONFIG_EVA) && \
+ defined(CONFIG_CPU_HAS_PREFETCH))
+#define DADDI_SCRATCH "$3"
+#else
+#define DADDI_SCRATCH "$0"
+#endif
+
+extern size_t __copy_user(void *__to, const void *__from, size_t __n);
+
+#define __invoke_copy_from(func, to, from, n) \
+({ \
+ register void *__cu_to_r __asm__("$4"); \
+ register const void __user *__cu_from_r __asm__("$5"); \
+ register long __cu_len_r __asm__("$6"); \
+ \
+ __cu_to_r = (to); \
+ __cu_from_r = (from); \
+ __cu_len_r = (n); \
+ __asm__ __volatile__( \
+ ".set\tnoreorder\n\t" \
+ __MODULE_JAL(func) \
+ ".set\tnoat\n\t" \
+ __UA_ADDU "\t$1, %1, %2\n\t" \
+ ".set\tat\n\t" \
+ ".set\treorder" \
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
+ : \
+ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
+ DADDI_SCRATCH, "memory"); \
+ __cu_len_r; \
+})
+
+#define __invoke_copy_to(func, to, from, n) \
+({ \
+ register void __user *__cu_to_r __asm__("$4"); \
+ register const void *__cu_from_r __asm__("$5"); \
+ register long __cu_len_r __asm__("$6"); \
+ \
+ __cu_to_r = (to); \
+ __cu_from_r = (from); \
+ __cu_len_r = (n); \
+ __asm__ __volatile__( \
+ __MODULE_JAL(func) \
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
+ : \
+ : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
+ DADDI_SCRATCH, "memory"); \
+ __cu_len_r; \
+})
+
+#define __invoke_copy_from_kernel(to, from, n) \
+ __invoke_copy_from(__copy_user, to, from, n)
+
+#define __invoke_copy_to_kernel(to, from, n) \
+ __invoke_copy_to(__copy_user, to, from, n)
+
+#define ___invoke_copy_in_kernel(to, from, n) \
+ __invoke_copy_from(__copy_user, to, from, n)
+
+#ifndef CONFIG_EVA
+#define __invoke_copy_from_user(to, from, n) \
+ __invoke_copy_from(__copy_user, to, from, n)
+
+#define __invoke_copy_to_user(to, from, n) \
+ __invoke_copy_to(__copy_user, to, from, n)
+
+#define ___invoke_copy_in_user(to, from, n) \
+ __invoke_copy_from(__copy_user, to, from, n)
+
+#else
+
+/* EVA specific functions */
+
+extern size_t __copy_from_user_eva(void *__to, const void *__from,
+ size_t __n);
+extern size_t __copy_to_user_eva(void *__to, const void *__from,
+ size_t __n);
+extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
+
+/*
+ * Source or destination address is in userland. We need to go through
+ * the TLB
+ */
+#define __invoke_copy_from_user(to, from, n) \
+ __invoke_copy_from(__copy_from_user_eva, to, from, n)
+
+#define __invoke_copy_to_user(to, from, n) \
+ __invoke_copy_to(__copy_to_user_eva, to, from, n)
+
+#define ___invoke_copy_in_user(to, from, n) \
+ __invoke_copy_from(__copy_in_user_eva, to, from, n)
+
+#endif /* CONFIG_EVA */
+
+static inline unsigned long
+raw_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ if (eva_kernel_access())
+ return __invoke_copy_to_kernel(to, from, n);
+ else
+ return __invoke_copy_to_user(to, from, n);
+}
+
+static inline unsigned long
+raw_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ if (eva_kernel_access())
+ return __invoke_copy_from_kernel(to, from, n);
+ else
+ return __invoke_copy_from_user(to, from, n);
+}
+
+#define INLINE_COPY_FROM_USER
+#define INLINE_COPY_TO_USER
+
+static inline unsigned long
+raw_copy_in_user(void __user*to, const void __user *from, unsigned long n)
+{
+ if (eva_kernel_access())
+ return ___invoke_copy_in_kernel(to, from, n);
+ else
+ return ___invoke_copy_in_user(to, from, n);
+}
+
+extern __kernel_size_t __bzero_kernel(void __user *addr, __kernel_size_t size);
+extern __kernel_size_t __bzero(void __user *addr, __kernel_size_t size);
+
+/*
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+static inline __kernel_size_t
+__clear_user(void __user *addr, __kernel_size_t size)
+{
+ __kernel_size_t res;
+
+#ifdef CONFIG_CPU_MICROMIPS
+/* micromips memset / bzero also clobbers t7 & t8 */
+#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$15", "$24", "$31"
+#else
+#define bzero_clobbers "$4", "$5", "$6", __UA_t0, __UA_t1, "$31"
+#endif /* CONFIG_CPU_MICROMIPS */
+
+ if (eva_kernel_access()) {
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, $0\n\t"
+ "move\t$6, %2\n\t"
+ __MODULE_JAL(__bzero_kernel)
+ "move\t%0, $6"
+ : "=r" (res)
+ : "r" (addr), "r" (size)
+ : bzero_clobbers);
+ } else {
+ might_fault();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, $0\n\t"
+ "move\t$6, %2\n\t"
+ __MODULE_JAL(__bzero)
+ "move\t%0, $6"
+ : "=r" (res)
+ : "r" (addr), "r" (size)
+ : bzero_clobbers);
+ }
+
+ return res;
+}
+
+#define clear_user(addr,n) \
+({ \
+ void __user * __cl_addr = (addr); \
+ unsigned long __cl_size = (n); \
+ if (__cl_size && access_ok(__cl_addr, __cl_size)) \
+ __cl_size = __clear_user(__cl_addr, __cl_size); \
+ __cl_size; \
+})
+
+extern long __strncpy_from_kernel_asm(char *__to, const char __user *__from, long __len);
+extern long __strncpy_from_user_asm(char *__to, const char __user *__from, long __len);
+
+/*
+ * strncpy_from_user: - Copy a NUL terminated string from userspace.
+ * @dst: Destination address, in kernel space. This buffer must be at
+ * least @count bytes long.
+ * @src: Source address, in user space.
+ * @count: Maximum number of bytes to copy, including the trailing NUL.
+ *
+ * Copies a NUL-terminated string from userspace to kernel space.
+ *
+ * On success, returns the length of the string (not including the trailing
+ * NUL).
+ *
+ * If access to userspace fails, returns -EFAULT (some data may have been
+ * copied).
+ *
+ * If @count is smaller than the length of the string, copies @count bytes
+ * and returns @count.
+ */
+static inline long
+strncpy_from_user(char *__to, const char __user *__from, long __len)
+{
+ long res;
+
+ if (eva_kernel_access()) {
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ "move\t$6, %3\n\t"
+ __MODULE_JAL(__strncpy_from_kernel_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (__to), "r" (__from), "r" (__len)
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
+ } else {
+ might_fault();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ "move\t$6, %3\n\t"
+ __MODULE_JAL(__strncpy_from_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (__to), "r" (__from), "r" (__len)
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
+ }
+
+ return res;
+}
+
+extern long __strnlen_kernel_asm(const char __user *s, long n);
+extern long __strnlen_user_asm(const char __user *s, long n);
+
+/*
+ * strnlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ *
+ * Context: User context only. This function may sleep if pagefaults are
+ * enabled.
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ * If the string is too long, returns a value greater than @n.
+ */
+static inline long strnlen_user(const char __user *s, long n)
+{
+ long res;
+
+ might_fault();
+ if (eva_kernel_access()) {
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_kernel_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
+ } else {
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
+ }
+
+ return res;
+}
+
+#endif /* _ASM_UACCESS_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 03:53:11 +0000